Regular Expressions 101

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An explanation of your regex will be automatically generated as you type.
Detailed match information will be displayed here automatically.
  • All Tokens
  • Common Tokens
  • General Tokens
  • Anchors
  • Meta Sequences
  • Quantifiers
  • Group Constructs
  • Character Classes
  • Flags/Modifiers
  • Substitution
  • A single character of: a, b or c
    [abc]
  • A character except: a, b or c
    [^abc]
  • A character in the range: a-z
    [a-z]
  • A character not in the range: a-z
    [^a-z]
  • A character in the range: a-z or A-Z
    [a-zA-Z]
  • Any single character
    .
  • Alternate - match either a or b
    a|b
  • Any whitespace character
    \s
  • Any non-whitespace character
    \S
  • Any digit
    \d
  • Any non-digit
    \D
  • Any word character
    \w
  • Any non-word character
    \W
  • Non-capturing group
    (?:...)
  • Capturing group
    (...)
  • Zero or one of a
    a?
  • Zero or more of a
    a*
  • One or more of a
    a+
  • Exactly 3 of a
    a{3}
  • 3 or more of a
    a{3,}
  • Between 3 and 6 of a
    a{3,6}
  • Start of string
    ^
  • End of string
    $
  • A word boundary
    \b
  • Non-word boundary
    \B

Regular Expression
No Match

@"
"
gmnxs

Test String

Code Generator

Generated Code

#include <StringConstants.au3> ; to declare the Constants of StringRegExp #include <Array.au3> ; UDF needed for _ArrayDisplay and _ArrayConcatenate Local $sRegex = "(?mnxs)(?mnxs-i)" & @CRLF & _ "^" & @CRLF & _ "(?!$)" & @CRLF & _ "(?<Thousands>" & @CRLF & _ " M{0,3}" & @CRLF & _ ")" & @CRLF & _ "(?<Hundreds>" & @CRLF & _ " (" & @CRLF & _ " (C(M|D))" & @CRLF & _ " (?!C)" & @CRLF & _ " |" & @CRLF & _ " D" & @CRLF & _ " )?" & @CRLF & _ " C{0,3}" & @CRLF & _ ")" & @CRLF & _ "(?<Tens>" & @CRLF & _ " (" & @CRLF & _ " (X(C|L))" & @CRLF & _ " (?!X)" & @CRLF & _ " |" & @CRLF & _ " L" & @CRLF & _ " )?" & @CRLF & _ " X{0,3}" & @CRLF & _ ")" & @CRLF & _ "(?<Ones>" & @CRLF & _ " (" & @CRLF & _ " (I(X|V))" & @CRLF & _ " (?!I)" & @CRLF & _ " |" & @CRLF & _ " V" & @CRLF & _ " )?" & @CRLF & _ " I{0,3}" & @CRLF & _ ")" & @CRLF & _ "$" Local $sString = "MMMDCCCLXXXVIII" & @CRLF & _ "MMMCDXLIV" & @CRLF & _ "" & @CRLF & _ "50 Valid" & @CRLF & _ "I" & @CRLF & _ "MMMCMXCIX" & @CRLF & _ "MMDCLXXIV" & @CRLF & _ "MCDXCIX" & @CRLF & _ "CCCXVIII" & @CRLF & _ "XCII" & @CRLF & _ "MMMLXXXIV" & @CRLF & _ "MMMCMLIII" & @CRLF & _ "DCCXXX" & @CRLF & _ "DCXCV" & @CRLF & _ "CCXCV" & @CRLF & _ "MMDCLX" & @CRLF & _ "MDCCLXXVI" & @CRLF & _ "CDXLV" & @CRLF & _ "MMMCDXLII" & @CRLF & _ "CMXXI" & @CRLF & _ "MDCCCXC" & @CRLF & _ "MMCCCXLVII" & @CRLF & _ "MCMXXXVIII" & @CRLF & _ "CDXCII" & @CRLF & _ "MMMCMXXII" & @CRLF & _ "DCXLVIII" & @CRLF & _ "MCDLVI" & @CRLF & _ "DCCLXXXIX" & @CRLF & _ "MMXIV" & @CRLF & _ "MCMXC" & @CRLF & _ "CCCLXXI" & @CRLF & _ "MDCCCXXI" & @CRLF & _ "MMCMLIV" & @CRLF & _ "MDCXVI" & @CRLF & _ "MMCMXLV" & @CRLF & _ "MCDLXXIX" & @CRLF & _ "DCCCXIII" & @CRLF & _ "CCXLVII" & @CRLF & _ "MDCCCXCV" & @CRLF & _ "MMCMLXXXVIII" & @CRLF & _ "CDLX" & @CRLF & _ "MMCDLIII" & @CRLF & _ "CMXLV" & @CRLF & _ "DCCXXII" & @CRLF & _ "MMMDCCL" & @CRLF & _ "CDXXVIII" & @CRLF & _ "MMDXLII" & @CRLF & _ "DCCCXCIX" & @CRLF & _ "MMXLI" & @CRLF & _ "CMXLIX" & @CRLF & _ "MCDXXXIX" & @CRLF & _ "" & @CRLF & _ "50 Invalid" & @CRLF & _ "IIII" & @CRLF & _ "VV" & @CRLF & _ "LL" & @CRLF & _ "DD" & @CRLF & _ "XXXX" & @CRLF & _ "CCCC" & @CRLF & _ "MMMM" & @CRLF & _ "IIV" & @CRLF & _ "IIIV" & @CRLF & _ "VX" & @CRLF & _ "VL" & @CRLF & _ "VC" & @CRLF & _ "XD" & @CRLF & _ "XM" & @CRLF & _ "IL" & @CRLF & _ "IC" & @CRLF & _ "ID" & @CRLF & _ "IM" & @CRLF & _ "MCMC" & @CRLF & _ "IXX" & @CRLF & _ "XCC" & @CRLF & _ "IIC" & @CRLF & _ "CDM" & @CRLF & _ "CDC" & @CRLF & _ "MIM" & @CRLF & _ "IXL" & @CRLF & _ "ILX" & @CRLF & _ "ICX" & @CRLF & _ "IICM" & @CRLF & _ "IIIC" & @CRLF & _ "IIIM" & @CRLF & _ "XIC" & @CRLF & _ "XIXX" & @CRLF & _ "XIXC" & @CRLF & _ "IXXC" & @CRLF & _ "CMCM" & @CRLF & _ "CDCD" & @CRLF & _ "XCXC" & @CRLF & _ "XLXL" & @CRLF & _ "MDCM" & @CRLF & _ "DCD" & @CRLF & _ "IXXL" & @CRLF & _ "XLC" & @CRLF & _ "VIX" & @CRLF & _ "VID" & @CRLF & _ "VIL" & @CRLF & _ "IIVX" & @CRLF & _ "IVXL" & @CRLF & _ "MXLIVC" & @CRLF & _ "CXM" & @CRLF & _ "" Local $aArray = StringRegExp($sString, $sRegex, $STR_REGEXPARRAYGLOBALFULLMATCH) Local $aFullArray[0] For $i = 0 To UBound($aArray) -1 _ArrayConcatenate($aFullArray, $aArray[$i]) Next $aArray = $aFullArray ; Present the entire match result _ArrayDisplay($aArray, "Result")

Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm